In the film, time travel will be invented – but it will be illegal and only available on the black market. When the mob wants to get rid of someone, they will send their target 30 years into the past, where a “looper” – a hired gun, like Joe (Gordon-Levitt) – is waiting to mop up. Joe is getting rich and life is good… until the day the mob decides to “close the loop,” sending back Joe’s future self (Willis) for assassination.